1. Field of the Invention
The present invention relates generally to copying machines, and more specifically, to a copying machine having a function of calling a control center by automatically activating a communication terminal such as a modem when a trouble is detected, and transmitting data related to the trouble after a connection with the control center is made.
2. Description of the Related Art
A system of controlling a plurality of copying machines is disclosed in U.S. Pat. No. 4,583,834. In the disclosed system, various kinds of information on copying machines such as the total number of copies, troubles, the remaining amounts of copy sheets and toner is transmitted to a computer. The computer processes the transmitted information and feeds back instructions to the copying machines.
According to such a system, a plurality of copying machines supplied to users are connected to a centralized control unit through a communication network such as telephone lines for remote control of the copying machines. The centralized control unit is provided at an administrators place and the administrator receives information transmitted from each of the copying machines with the centralized control unit. Then, various administrative works are done such as issuance of bills corresponding to the numbers of copies and dispatch of servicemen to cope with troubles.
Since a general copying machine does not have a function of communicating with a centralized control unit through a communication network, a data terminal is attached to a copying machine for communication when such a system is constructed. The data terminal collects various kinds of information from the copying machine and communicates with the centralized control unit based on the collected information.
The data terminal calls the centralized control unit when a trouble occurs in the copying machine, but a communication is not necessarily executed. For example, if the data terminal is defective or the communication line is busy, a communication between the data terminal and the centralized control unit can not be executed. Meanwhile, believing that the occurrence of a trouble in the copying machine is automatically reported to the centralized control unit from the data terminal, the user does not contact the administrator right away. Accordingly, it some times takes a long time before the administrator is informed of the trouble in the copying machine.
Conversely, it is useless for the user to report to the administrator if the data terminal has reported the occurrence of the trouble to the centralized control unit.